Mixer for explosives



(No Model.)

W. R. QUINAN.

UNITED STATES ATENT Fries.

XVILLIAM R. QUINAN, OF PINOLE, CALIFORNIA.

iVliXER FOR EXPLOSIVES.

SPECIFICATION forming part of Letters Patent No. 427,707, dated May 13,1890.

Application filed December 20, 1889. Serial No. 334,426. (No model.)

To to whom it may concern:

Be it known that I, WILLIAM R. QUINAN, a citizen of the United States,residing at Pinole, Contra Costa county, State of California, haveinvented an Improvement in Apparatus for Mixing Gunpowder and Dynamite;and I hereby declare the following to be a full, clear, and exactdescription of the same.

My invention i-elates to the class of mechanisms used in the art ofmaking gunpowder and dynamite; and it consists of a steamjacketed tubethrough which the composition is passed and a stirrer, conveyor, ormixer operating within the tube, as will be hereinafter fully described,and the novelty specifically pointed out in the claims.

The object of my invention is to produce cheaply and continuously acomposition which is to be used directly as an explosive or as a dope towhich a percentage of nitroglycerine or other explosive is to be addedto give it the necessary explosiveness.

My invention relates only to compositions which contain one or moreingredients that can be melted or softened by a moderate heat, whichingredient serves to cement or aggregate the particles of thecomposition into grains. My apparatus is designed to melt or soften thisingredient and mix it with the others, so as to form by continuousprocess a plastic mass which can be readily grained. In ordinarygunpowder or black blastingpowder the sulphur is such an ingredient. Myapparatus can also be used in preparing the dope for certain classes ofdynamites, especially low dynamites or those which contain a smallpercentage of nitro-glycerine. In these sulphur maybe used as aningredient; also, resin, parafline, asphaltum, and various othersubstances which serve the purpose desired.

In preparing fire-explosivessuch as gunpowder-the ingredients should bepulverized as finely as possible and mixed in the proper proportionsbefore being passed through my apparatus. The finer the materials themore intimate the incorporation effected by the apparatus and the betterthe powder.

In making the dope for dynamites or other detonating explosives theingredients need not be ground fine, but should be mixed properproportions.

My apparatus may vary considerably in detail.

The accompanying drawing, which is a part section and part elevation,represents a typical example, though I do not confine myself to thedimensions given nor the exact arrangement of the minor parts. Itconsists of a metal tube A-say three inches in diameter and about tenfeet long. This maybe apiece of thin boiler-tubing. This is jacketedwith a larger tube Bsay four and onehalf inches in diameter of about thesame length, with steanrtight joints at the ends. The tube B is coveredwith a good non-conducting coating such as is used on steam-boilers.Inside of the inner tube A is a stirrer, conveyer, or mixer C,consisting of a shaft or piece of pipe studded for the greater part ofits length with pins about one and one-fourth inch apart, set spirallyaround the shaft. The pins extend beyond the inner tube at both ends andare of such length that their ends just clear the inside surface of theinner tube A. A hopperD is placed at the upper end of the tube. Theapparatus is set at an incline of about forty degrees with thehorizontal. The stirrer is revolved by a pulley E and wire rope F aboutone hundred and twenty revolutions a minute, and at the same time, byany usual device-sueh as is shown by the cam or eccentric at II-is givena short reciprocal motion in the tube, this to enable the pins to reachall parts of the tube and prevent the composition from clogging. Thespace between the inner and outer tubes is connected with asteam-boiler. Steam at forty or fifty pounds pressure is allowed toenter through the connection S, and the condensed water is drawn off atT.

In operating the apparatus the composition is placed in the hopper D.The revolution of the stirrer, assisted by gravity, causes it to movethrough the tube, which is heated by the steam. The steam is regulatedby the gage G, which should be kept, say, at forty pounds. In this way atemperature of about 248 Fahrenheit can be maintained in the tube andthe composition heated to about this point. This causes the sulphur tomelt and permeate the mass, a thorough mixing or incorporation beingeffected with the stirrer. The plastic and pulverulent composition flowsout of the tube at the lower end and may be received upon sieves andgranulated. If during this operation it is cooled slightly, which may beeffected by allowing it to roll down an inclined plate below the sieves,the individual grains will not stick to each other, but will remainseparate. The foregoing applies specially to sulphur compositions. Thesteam-pressure and consequenttemperature can be suitably modified forthe fusion of other substances.

The capacity of the apparatus will depend upon various circumstances.The larger the tube the greater the amount of composition which canbe'heated at one time. The steeper the tube is set or the more rapidlythe stirrer is revolved the faster the composition will pass through;but if it comes too fast the sulphur will not be properly melted. Thiscase may be met by raising the steam-pressure or diminishing the feed.It is advisable, however,

not to use steam above fifty or sixty pounds,

both on account of the danger of too high a temperature and because thesulphur, if overheated, becomes stiff and viscous. It will be found thatthe composition flows best at a temperature of about 248. It is betterto get the requisite capacity by mounting a number of tubes.

The advantages are simplicity and cheapness of plant and continuity ofprocess; also, little or no skill is required to work the apparatus. Thesteam-gage is a simple and reliable guide to the workman.

In regard to gunpowder made with this apparatus, if it has the usualcomposition, it must be considered as a crude cheap product. The grainsare light and porous. For general purposes it cannot compete with thatmade by more expensive processes; but there are compositions in whichstronger oxidizing agents are used than in gunpowder. The apparatusserves a good purpose in preparing these. In preparing the dope for lowdynamites it has many advantages, giving a fairlygrained powder and onewhich resists the attack of moisture better than usual. The expense forsteam in this method is quite small. If the materials are dry, as theyshould be when put in the tube, the amount of steam consumed is thatrequired to heat the composition to 248 Fahrenheit and melt the sulphur.The specific heat of powder ingredients is small, and so also is thelatent heat of sulphur. Taking an ordinary composition I have calculatedthat one pound weight of steam at forty pounds pressure will raise thetemperature of the ingredients from to 248 Fahrenheit and melt thesulphur in twenty pounds of composition. With good coverings for thesteam-pipes the loss of heat should not exceed ten per cent. If thematerials are Warm as well as dry, which can be readily managed by usingthe niter fresh from the drying process, the steam consumed by keepingthe gage at forty pounds will be still further reduced. As a pound ofsteam at this pressure can be ordinarily generated with about one-sixthof a pound of coal, the fuel expense is very moderate.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. A powder-mixing apparatus consisting of a steam-jacketed tube throughwhich the composition is passed, a stirrer, conveyer, or mixer withinthe tube, and means for rotating and longitudinally reciprocating saidstirrer, conveyer, or mixer, substantially as herein described.

2. A powder-mixing apparatus consisting of a steam-jacketed tube throughwhich the composition is passed, a stirrer, conveyer, or mixer withinthe tube, means for rotating said stirrer, conveyer, or'mixer, and a camor eccentric for imparting a reciprocal movement to the same,substantially as described.

3. A powder-mixing apparatus consisting of a steam-jacketed tube throughwhich the composition is passed, a hopper at the inlet end of said tubefor supplying the material thereto, and a stirrer, conveyer, or mixeroperating within the tube, said stirrer having an axial and shortlongitudinal reciprocating movement, substantially as herein described.

In witness whereof I have hereunto set my hand.

\VILLIAM R. QUINAN.

\Vitnesses:

J. P. BARRETT, A. J. WILLsoN.

